Record PendingTaskCount when a backgrounded renderer is suspended.

third_party/WebKit/Source/platform/scheduler/child/idle_helper.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/scheduler/child/idle_helper.h"
 
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "platform/scheduler/base/real_time_domain.h"
@@ skipping 454 matching lines @@
     case IdlePeriodState::IN_LONG_IDLE_PERIOD_WITH_MAX_DEADLINE:
       return "in_long_idle_period_with_max_deadline";
     case IdlePeriodState::IN_LONG_IDLE_PERIOD_PAUSED:
       return "in_long_idle_period_paused";
     default:
       NOTREACHED();
       return nullptr;
   }
 }
 
+int IdleHelper::GetNumberOfPendingIdleTasks() {
+  return idle_queue_->GetNumberOfPendingTasks();
+}
+
 }  // namespace scheduler
 }  // namespace blink